[TPU][V1][DEBUG] Provide Env Variable To Disable Sampler

[NickLucche]

Just continuing @robertgshaw2-redhat work from #15662.
This should be ready, let's wait for tests to confirm it.

cc @yaochengji

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[NickLucche]

As always, thanks for reviewing!

[yaochengji]

LGTM, thanks!

[mergify]

This pull request has merge conflicts that must be resolved before it can be
merged. Please rebase the PR, @NickLucche.

https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/working-with-forks/syncing-a-fork

[NickLucche]

closing in favor of #16275